import { INCREMENTCOUNT,DECREMENTCOUNT } from "../constant/countConst"


//定义一个初始值
const init = {
    count:0
}

export default function countReducer(prevStata=init,action){
    console.log('rreducer调用了');
    //接受action对象的type和data
    const {
        type,data
    }=action;
    switch (type) {
        case INCREMENTCOUNT:
            return {
                ...init,count:prevStata.count+data
            };

        case DECREMENTCOUNT:
            return {
                 ...init,count:prevStata.count-data
        };
    }
    return prevStata;
}